Alkyl-alkanol amine salts of alkylated aryl sulfonic acids



Patented Aug. 10, 1954 ALKYL-ALKANOL AMINE SALTS OF ALKYL- ATED ARYLSULFONIC ACIDS Vincent J. Keenan, Ardmore, Pa., assignor to The AtlanticRefining Company, Philadelphia, Pa., a corporation of Pennsylvania NoDrawing. Application January 23, 1952, Serial No. 267,927

11 Claims.

This invention relates to new amine salts of alkylated aryl sulfonicacids having excellent Wetting, foam, and detergent characteristics, andrelate more particularly to alkyl-alkanol amine salts of alkylatedbenzene sulfonic acids, the alkyl group of such acids containing from 9to carbon atoms and preferably an average of 12 carbon atoms. Suchcompounds have exceptional utility in dishwashing.

Recently a number of liquid detergents have been synthesized which arewater-soluble and consequently useful in washing dishes and similarcleaning processes. While such materials have met with some commercialsuccess, some are not entirely satisfactory because of their relativelylow Water solubility and poor cleaning power. In an effort to improveupon these heretofore known synthetic detergents, I producedalkanolamine salts of alkylarylsulfonic acids such, for example, as thetri-ethanolamine salts of alkylated benzene sulfonic acids. Suchcompounds are of particular value for household liquid detergentsbecause of their high water solubility and rinsability.

I have discovered that if at least one of the alkanol groups on thetrialkanol amine salts of alkyl aryl sulfonic acid is replaced by analkyl group, new compositions are obtained which are less soluble inwater but, surprisingly, markedly better detergents for proteinaceousand fatty soils and mixtures thereof.

They are less irritating to the skin than the corresponding inorganicsoaps. These new compounds have exceptional utility in washing dishes,not only because of their improved detergency, but likewise because oftheir superior foaming power and foam stability. The latter iparticularly important in the economical use of such detergents, sinceit furnishes the user with a measure of the residual detergent availablein the Wash solution, e. g., a dishpan, throughout the cleansingoperation.

In accordance with the present invention, the new amine salts may beproduced simply by neutralizing, or reacting a theoreticalstoichiometric amount of, an alkyl benzenesulfonic acid or acid mixturewith an alkylalkanol amine.

The amines used in the production of the new compounds include the alkyldialkanol amines and the dialkylalkanol amines in which the alkyl groupor groups contain from 1 to 6 carbon atoms and the alkanol group orgroups are the lower alkanols containing 2 or 3 carbons atoms such, forexample, as ethanol, n-propanol, or isopropanol. Such alkylalkanolamines can be prepared by various methods, as for example, by thereaction of an alkylene oxide with an alkyl amine, and many of thesematerials are commercially available. Specific examples of thealkylalkanol amines herein contemplated as suitable for the preparationof the new compounds of the present invention are methyldiethanol amine,ethyldiethanol amine, n-propyldiethanol amine, n-butyldiethanol amine,isopropyldiethanol amine, isobutyldiethanol amine, amyldiethanol amine,hexyldiethanol amine, dimethylethanol amine, diethylethanol amine,dipropylethanol amine, dibutylethanol amine, diamylethanol amine,methyldipropanol amine, ethyldipropanol amine, propyldipropanol amine,butyldipropanol amine, amyldipropanol amine, hexyldipropanol amine,dimethyl n propanol amine, dimethylisopropanol amine, diamyl-nropanolamine, diamylisopropanol amine, methylethylethanol amine,amylethylethanol amine, ethylpropyl-n-propanol amine, andethylpropylisopropanol amine. Is is to be understood that the alkylgroups in the case of a dialkylalkanol amine may be similar ordissimilar, as desired. The same is true of the alkanol groups in analkyldialkanol amine.

The alkylarylsulfonic acids or acid mixtures which are neutralized, inaccordance with this invention, to produce the new amine salts havingexceptional utility in dishwashing are those obtained by sulfonation ofalkylated benzenes or benzene mixtures having from 9 to 15 carbon atomsin the alkyl group, and preferably averaging about 12 carbon atoms inthe alkyl group. In addition to the long chain alkyl group, othernuclear hydrogen atoms of the aromatic may be substituted by alkylgroups having from 1 to 3 carbon atoms. These sulfonic acids may bereadily prepared by sulfonating appropriate alkylated benzenehydrocarbons or hydrocarbon mixtures using sulfuric acid of about 98% to99 concentration or higher and then separating the spent sludgecontaining free sulfuric acid from the desired sulfonic acid by settlingand decanting or other suitable methods. The resulting sulfonic acidpreferably is further purified by dissolving the same in benzene,octane, or other convenient solvent and decanting or otherwise removingthe additional sludge which is thereby separated. The solvent may beremoved from the sulfonic acid by evaporation or other methods eitherprior or subsequent to neutralization or reaction of the sulfonic acidwith the alkylalkanol amine.

As previously stated, the alkyl benzene hydrocarbon or hydrocarbonmixtures which are sulfonated to provide the necessary sulfonic acidsfor neutralization have an alkyl group containing from 9 to 15 carbonatoms and the remaining nuclear substitue-nts of the benzene radical areselected from the group consisting of hydrogen and lower alkyl groupshaving from 1 to 3 carbon atoms. In all cases, however, the arylhydrocarbon may be one or a mixture of two or more hydrocarbons such asbenzene, toluene, xylene, ethyl benzene, propyl benzene, and isopropylbenzene.

Specific examples of the alkyl aromatic hydrocarbons herein contemplatedas suitable for the invention are nonyl benzene, nonyl toluene, nonylethyl benzene, nonyl propyl benzene, nonyl dimethyl benzene, nonyldiethyl benzene, nonyl methyl ethyl benzene, nonyl methyl prop lbenzene, nonyl ethyl propyl benzene, nonyl dipropyl benzene, decylbenzene, decyl toluene, decyl ethyl benzene, decyl propyl benzene, decyldimethyl benzene, decyl diethyl benzene, decyl methyl ethyl benzene,decyl methyl propyl benzene, decyl ethyl propyl benzene, decyl dipropylbenzene, undecyl benzene, undecyl toluene, undecyl ethyl benzene,undecyl dimethyl benzene, undecyl diethyl benzene, undecyl methyl ethylbenzene, undecyl methyl propyl benzene, undecyl dipropyl benzene,dodecyl benzene, dodecyl toluene, dodecyl ethyl benzene, dodecyl propylbenzene, dodecyl dimethyl benzene, dodecyl diethyl benzene, dodeoylmethyl ethyl benzene, dodecyl methyl propyl benzene, dodecyl diprcpylbenzene, trideoyl benzene, tridecyl toluene, tridecyl ethyl benzene,tridecyl propyl benzene, tridecyl dimethyl benzene, tridecyl diethylbenzene, tridecyl methyl ethyl benzene, tridecyl methyl propyl benzene,tridecyl dipropyl benzene, tetradecyl benzene, tetradecyl toluene,tetradecyl ethyl benzene, tetradecyl propyl benzene, tetradecyl dimethylbenzene, tetradecyl diethyl benzene, tetradecyl methyl ethyl benzene,tetradecyl methyl propyl benzene, tetradecyl dipropyl benzene,pentadecyl benzene, pentadecyl toluene, pentadecyl ethyl benzene,pentadecyl propyl benzene, pentadecyl dimethyl benzene, pentadecyldiethyl benzene, pentadecyl methyl ethyl benzene, pentadecyl methylpropyl benzene, and pentadecyl dipropyl benzene, or mixtures thereof.

The production of the alkylated benzenev hydrocarbons or hydrocarbonmixtures may be accomplished by various methods such, for example, as byreacting a chlorinatedalkyl hydrocarbon or hydrocarbon mixture having 9to 15 carbon atoms with the aromatic hydrocarbon in the presence of aFriedel-Crafts catalyst such as AlCla. The alkyl halide may be obtainedby chlorinating the proper petroleum fraction such as a kerosenefraction. The aromatic hydrocarbon may be benzene, toluene, xylene,ethyl benzene, propyl benzene, and ispropyl benzene.

Preferably, however, the benzene hydrocarbon may be alkylated with amono-olefin polymer or mixture of polymers containing from 9 to 15carbon atoms in the presence of a suitable catalyst such as sulfuricacid, A1013, SnCl4, ZnCh, BF3, or HF. The olefin polymer or polymermixture is most suitably derived by subjecting a lower olefin topolymerizing conditions in the presence of a catalyst such as phosphoricacid impregnated on a carrier such as kieselguhr. Propylene or gaseousmixtures containing substantial amounts of propylene is preferred.Mixtures of propylene and propylene dimers or trimers may also be used.

' It is desirable, however, that readily polymerizable olefins such asisobutylene be absent inasmuch as the resulting polymers easilydepolymerize under alkylating conditions, and produce alkylated arylhydrocarbons in which the alkyl group or groups are of short chainlength. Most convenient and economic for use are petroleum refinery gasstreams which have been fractionated to remove all or substantially allof the butane, butenes, and heavier hydrocarbons. For example, arefinery gas stream comprising 4.6 mol per cent methane, 5.2 mol percent ethylene, 19.5 mol per cent ethane, 26.2 mol per cent propylene,and 44.5 mol per cent propane may be contacted with a supportedphosphoric acid catalyst at 300 F. to 600 F. under a pressure between200 and 1800 p. s. i., employing a space velocity of 0.05 to 0.15 lb.mols of propylene per lb. of catalyst per hour. The resulting polymerswill comprise a complex mixture of olefinic hydrocarbons containing from6 to about 18 carbon atoms per molecule, and these polymers will notconsist solely of dimers, trimers, pentamers, etc., but will include C7,C8, C10, C11, C13, C14, and slightly higher polymers due to theinterpolymerization of propylene polymer degradation products as well asthe presence, in most cases, of ethylene which may be interpolymerized.The polymer mixture may also contain minor amounts of paraffins ofvarious molecular weights as by-products of the polymerization reaction.Preferred conditions for polymerization require temperatures between 300F. and 500 F. under pressures of 300 to 1000 p. s. i. at a spacevelocity of about 0.004 lb. mols of propylene per lb. of phosphoric acidcatalyst per hour. To obtain a, preponderance of polymers averaging 9carbon atoms, high pressures and high space velocities are desirable, i.e., 1000 to 1800 p. s. i. and 0.006 space velocity. On the other hand,to obtain high yields of polymers averaging 12 carbon atoms with minoramounts of polymers averaging 15 carbon atoms, somewhat lower pressuresand space velocities should be used, for example, 200 to 800 p. s. i.and 0.002 to 0.004 space velocity. Depending upon the average chainlength or molecular weight of the polymers desired for the alkylation ofthe aryl hydrocarbon, the crude propylene polymers may be fractionallydistilled to obtain the necessary fraction or fractions, and these maybe either distillates or distillation residues.

A polymer fraction may be mixed, for example, with 5 to 6 molarequivalents of benzene and 0.05 to 0.1 molar equivalents of a catalystsuch as A1013, and the alkylation carried out at F. to 180 F. Thecatalyst then is separated from the alkylation mixture, the mixture iswashed with dilute alkali solution, settled, and washed to removealkali. The alkylation mixture is then fractionally distilled to removeexcess benzene, low boiling alkylated benzene resulting as degradationby-products, and small amounts of low boiling olefins and parafiins.

An alkylated aryl hydrocarbon mixture which is particularly useful inthe present invention may be obtained by reacting the above mentionedpropylene polymer fraction containing from 9 to 15 carbon atoms with anaromatic hydrocarbon and subsequently fractionating the alkylated arylhydrocarbon mixture to obtain a fraction consisting predominantly ofalkyl aromatics having 12 carbon atoms in the alkyl group, or,alternatively, the propylene polymer fraction having 9 to 15 carbonatoms may be fractionated to separate a narrow boiling cut consisting ofa major proportion of polymers having 12 carbon $686,201 as e atomswhich may subsequentlybe reactechwlth "cient quantity to substaritiallyneutralize the thearomatichydrocarbon to produce a m-ixture ac id was Aadded. The zrpercent :Lidetergency, mas ,of alkylated aromatics havingpredominantly-12 idete y ti s e fi' a I carbon atoms in the 'a,1ky1-gr0up, 3' for 0.-06%=-3l1d5 0.20%:concentrationsin lifit'pepdm.

Ifde'sirbd a combination of th'esetwo-methodshardwater. may be-used; i;-e.,"-fractionation of the"C9 to C propylene polymermixturepalkylationwith the A ""G1z'--cut,"their"fractionation of thealkylatedaroquantlty of the m m9 -P 'q in Example I was neutiahzed w1thpure. trimat1c mixture. -In all cases; howeve1,-the-alkyl- I p Vethanolamine. The-resulting product was.subatedaromatichydrocarbon-mixturewhich ls par- -10. b r I l 7 a ectcd tothe.York.d1shwash1ng "test andthe reticularly-useful contains a rumorproportion of I l I ,g sults thereof for 0.06 m and 00.20% concentraanalkylated aromatichydrocarbon havlng 12 ltions 100 p ,hard Watergiven-"in carbonatoms in thealkyl'group with very minor Table I *amountsof alkylated aromatics havingtalkyl Table I groups other than'-"12-carbons andwithin the 5 range'from 9; to 15 carbons. 1 .,Percent Thefol-lowing examples are given for the pur- Example Dctergency"Detergency H pose of further illustrating the present-invengg- 333 53-33 "tion,'-but'- are'not'intended to=-be' limiting-on the f scopether-eof. 'Ihe alkylalkanol amine sa'lts:20. I 53 produced in theexamples-in accordance with II III I:III mo 57 h thepresentinvention-were: subjected either to the York dishwashing test orto" 'an acc'elerated dishwashing test; as indicated. "-By way of com--*parison, the same-tests were. performed on the; wunsubstituted'alkanol amine -salts, -sp-ecifically triethanolamine s'alts;-ofthe:same. alk'ylatedbenzene sulfonic acids to show the very marked andunexpected superiority of the alkylalkanol amine salts for: dishwashing.

The. York dishwashingtest was made.in ..accordancewith theprocedureldescribed ibyMachlis .The above examples and dataclearlyshow..the .marked .and unexpected superiority, as edish- ....washing.compounds, of. the: alkylalkanolc amine .salts oflalkylated. benzene.sulfoniaacidsehaving to. .l5..carbon. atoms in :thealk-ylgroup oventheunsubstitutedialkanol aminasalts oisuchiacids. In addition, thealkylalkanolcamine.saltstofralkyl benzene .isulfonic acids .have verysatisfactory andnMichaels in"Soap, and.Sanitary;Chemicals, Water 3 n napowe "September 1948, pages'l-M. The...results of IV suchtest-are giveninjtheltable in termsiottheess gAuuantiW of the sU1flmicjyqawidiofiExamme I g s was neutralized aivith 'amyldiethariol aminea-and 'Z'Theaccelerated dishwashingtest involves'soll-,ethefresmbingfproduct,wasisubjectedgtmthejacceb ing' 8-inch whitechinadi'shes by first applying aerated.gdishwgishing=436st fl1 ts:jfgisuch to each dish 7 gms. of a blend of 71.5% fresh egg test arereported in Table IL and 28.5% bacon grease mixed in a Waring 40 Blendorand then drying the dishes in an oven, EXAMPLEZV maintained at 150 F.for 15 minutes. .After To a quantity of the sulfonic acid of Examplecooling to room temperature, the dishes are I was added suflicientn-butyldiethanol amine to washed one by one in an oval 14 by 18" by 15"neutralize the acid. The product was subjected dishpan containing 2000cc. of 100 p. p. m. hard to the accelerated dishwashing test and therewater solution having 0.15% concentration of the sults thereof aregiven in Table II.

detergent under investigation. Prior to placing EXAMPLE VI any dishes inthe water solution, it is agitated Another quantity of the sulfonic acidwas neu l h f 5 s Vlolent y by and or approxlmately 1 Second tralizedwith isobutyldiethanol amine. The

22 3 gggss gg i g h the foam breaks product was tested by theaccelerated dishwashdown and the end point is reached when no foam mgprocedure and the results are gwen m remains in the dishpan. Results ofthe test are Table reported as the number of dishes, each contain-EXAMPLE VII ing originally of Soil, leaned b ore a In this case,triethanol amine was used to neu- Ioam disappears. tralize a quantity ofthe sulfonic acid. The prod- This test has proven to have a high de ofnot was tested by the accelerated method and the reproducibility uponrepeated testing with a lt a presented in Table II,

. ivgrliietergent and among a variety of operators EXAMPLE. VIII EXAMPLEI A quantity of the sulfonic acid of Example I at was neutralized withdiethanol amine. The re- To quantity of Sulfonic acid prepared bysulting product was subjected to the accelerated sulfonation heart-cutalkylated benzene dishwashing test. The results of the test arepremlxture containing an average of 12 carbon sented in Table IL atomsin the alkyl group and produced as above Table H described, pureamyldiethanol amine was added in sufiicient quantity to substantiallyneutralize N I the acid. The resulting salt was subjected to E 1 g f theYork dishwashing tests and the results theremm 6 washg a of for 0.06%and 0.20% concentrations in 100 p. p. m. hard water are reported inTable I. 3

EXAMPLE II H 2 To a quantity of the same sulfonic acidas used VIII inExample I, n-butyldiethanol amine in suffi- The above examples andresulting data further show that alkylalkanol amine salts of alkylatedbenzene sulfonic acids having an alkyl group of from 9 to 15 carbonatoms are vastly superior as dishwashing compounds to unsubstitutedalkanol amine salts of such acids. The superiority of the alkyl alkanolamine is very marked and unexpected.

I claim:

1. A tertiary amine salt of an alkyl benzene sulfonic acid, the alkylradical of said acid having from 9 to 15 carbon atoms, and the remainingnuclear substituents of the benzene radical being selected from thegroup consisting of hydrogen and lower alkyl groups having from 1 to 3carbon atoms and the tertiary amine being selected from the groupconsisting of dialkyl alkanol amines and alkyl dialkanol amines, whereinthe alkyl substituents have from 1 to 6 carbon atoms and the alkanolsubstituents have from 2 to 3 carbon atoms.

2. An alkyl dialkanol amine salt of an alkyl benzene sulfonic acid, thealkyl radical of said acid having from 9 to 15 carbon atoms and theremaining nuclear substituents of the benzene radical being selectedfrom the group consisting of hydrogen and lower alkyl groups having from1 to 3 carbon atoms, the alkyl substituents of the amine having from 1to 6 carbon atoms, and the alkanol substituents of the amine having from2 to 3 carbon atoms.

3. A dialkyl alkanol amine salt of an alkyl benzene sulfonic acid, thealkyl radical of said acid having from 9 to 15 carbon atoms and theremaining nuclear substituents of the benzene radical being selectedfrom the group consisting of hydrogen and lower alkyl groups having from1 to 3 carbon atoms, the alkyl substituents of the 8 amine having from 1to 6 carbon atoms, and the alkanol substituents of the amine having from2 to 3 carbon atoms.

4. An amyldiethanol amine salt of an alkylbenzene sulfonic acid, thealkyl group of said acid having from 9 to 15 carbon atoms.

5. An n-butyldiethanol amine salt of an alkylbenzenesulfonic acid, thealkyl group of said acid having from 9 to 15 carobn atoms.

6. An isobutyldiethanol amine salt of an alkylbenzenesulfonic acid, thealkyl group of said acid having from 9 to 15 carbon atoms.

'7. An isopropyldiethanol amine salt of an alkylbenzenesulfonic acid,the alkyl group of said acid having from 9 to 15 carbon atoms.

8. An amyldiethanol amine salt of an alkylbenzenesulfonic acid in whichthe alkyl group averages 12 carbon atoms.

9. An n-butyldiethanol amine salt of an alkylbenzenesulfonic acid inwhich the alkyl group averages 12 carbon atoms.

10. An isobutyldiethanol amine salt of an alkylbenzenesulfonic acid inwhich the alky group averages 12 carbon atoms.

11. An isopropyldiethanol amine salt of an alkylbenzenesulfonic acid inwhich the alkyl group averages 12 carbon atoms.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,780,144 Reddish Oct. 28, 1930 2,085,298 De Groote -1 June29, 1937 2,204,326 Steik June 11, 1940 2,231,752 De Groote Feb. 11, 19412,467,132 Hunt et al Apr. 12, 1949 2,567,854 Nixon Sept. 11, 1951

1. A TERTIARY AMINE SALT OF AN ALKYL BENZENE SULFONIC ACID, THE ALKYLRADICAL OF SAID ACID HAVING FROM 9 TO 15 CARBON ATOMS, AND THE REMAININGNUCLEAR SUBSTITUENTS OF THE BENZENE RADICAL BEING SELECTED FROM THEGROUP CONISITING OF HYDROGEN AND LOWER ALKYL GROUPS HAVING FROM 1 TO 3CARBON ATOMS AND THE TERTIARY AMINE BEING SELECTED FROM THE GROUPCONSISTING OF DIALKYL ALKANOL AMINES AND ALKYL DIALKANOL AMINES, WHEREINTHE ALKYL SUBSTITUENTS HAVE FROM 1 TO 6 CARBON ATOMS AND THE ALKANOLSUBSTITUENTS HAVE FROM 2 TO 3 CARBON ATOMS.